At present, IPTV is commercially applied to the global market in a large scale. When services of an IPTV service system become inaccessible due to the upgrading, server failure or network failure, a Set Top Box (STB) cannot provide normal TV service for a user. A large scale of users may be greatly influenced since the IPTV service is a telecommunication level service. Moreover, a TV service, as the most important recreational activity for ordinary family life particularly in holidays, may be more greatly influenced.
For the above problem in a related technology, there is yet no effective solution.